Applied Mathematics Colloquium - Statistical mechanics of exotic liquid crystals

Speaker:   Elsen Tjhung (The Open University)

Abstract: The usual nematic phase in liquid crystals is formed by rod-shaped molecules. However, many liquid crystalline-forming molecules in nature are not straight. For instance, one can imagine banana-shaped or cone-shaped molecules, which can form various splay-bend phases. In this work, we predicted, theoretically, a new liquid crystalline phase, which we call splay-bend-infinity phase. This phase has an interesting optical property: 

it can split incoming light beam into two, which might have future technological applications in 3d displays and augmented reality. From the fundamental point of view, this new liquid crystalline phase also has a true long range order in 2d (in contrast to quasi-long range order in 2d nematics), in apparent contradiction to the Mermin-Wagner theorem.

Ref:   X. Ma and E. Tjhung, Banana- and pizza-slice-shaped mesogens give a new constrained O(n) ferromagnet universality class, Phys. Rev. E, 100, 012701